Gürson C T, Saner G
Am J Clin Nutr. 1978 Jul;31(7):1162-6. doi: 10.1093/ajcn/31.7.1162.
Since urine is the main excretory pathway for chromium, this study was conducted to compare in normal individuals the daily urinary chromium excretion with a 4 hr sample, to investigate diurnal fluctuations of urinary chromium and age-dependent relationship between urinary chromium and creatinine excretion. The results can be summarized as 1) there was no significant difference between the observed 24 hr chromium excretion and 24 hr excretion calculated from the one 4 hr samples, 2) a diurnal variation was observed when urinary excretion was expressed as chromium per minute, but no time-related variation could be established when chromium/creatinine (Cr/Cre) ratios in samples from three different periods of the same day were compared, although a significant positive correlation existed between urinary chromium and creatinine concentration, 3) the Cr/Cre ratio was found to be age-dependent, 4) in malnourished children the Cr/Cre ratio was very high and significantly different from that of normal infants, 5) This ratio for the eight diabetics was found to be significantly higher when compared with normal adults. On the basis of these results, it is suggested that morning 4 hr urinary chromium reflects the daily chromium excretion and that the Cr/Cre ratio of single urine samples obtained during this period is a reliable criterion in the evaluation of chromium nutrition of individuals in different conditions, provided that the influence of age is taken into consideration.
由于尿液是铬的主要排泄途径，本研究旨在比较正常个体24小时尿铬排泄量与4小时尿样中的排泄量，以研究尿铬的昼夜波动情况以及尿铬与肌酐排泄之间的年龄依赖关系。结果可总结如下：1）观察到的24小时铬排泄量与根据一个4小时样本计算出的24小时排泄量之间无显著差异；2）当以每分钟铬排泄量表示时观察到昼夜变化，但当比较同一天三个不同时间段样本中的铬/肌酐（Cr/Cre）比值时，未发现与时间相关的变化，尽管尿铬与肌酐浓度之间存在显著正相关；３）发现Cr/Cre比值与年龄有关；4）营养不良儿童的Cr/Cre比值非常高，且与正常婴儿的比值有显著差异；5）发现8名糖尿病患者的这一比值与正常成年人相比显著更高。基于这些结果，建议早晨4小时尿铬反映每日铬排泄量，并且在此期间获得的单次尿样的Cr/Cre比值是评估不同情况下个体铬营养状况的可靠标准，前提是考虑到年龄的影响。
